<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <div>
        <input type="text" value="" id="keyword" />
        <div id="keyDiv"></div>
        <div id="div1"></div>
    </div>
    <script>
        const oInput = document.getElementById('keyword');
        const oDiv = document.getElementById('keyDiv');
        const oDiv1 = document.getElementById('div1')
        const o = {
            keyword: 'LOL'
        }
        const hander = {
            get: function(target, key) {
                console.log('++++');
                return target[key];
            },
            set: function(target, key, value) {
                oDiv.innerText = value;
                div1.innerText = value;
                target[key] = value;
            }
        }
        const proxyObj = new Proxy(o, hander)
        window.onload = function() {

            oInput.value = proxyObj.keyword;
            oDiv.innerText = proxyObj.keyword;
            div1.innerText = proxyObj.keyword;
            oInput.addEventListener('input', function() {
                proxyObj.keyword = this.value
            })
        }
    </script>
</body>

</html>